CVE-2026-4636
Full vulnerability record from the local CVENow database.
Description
A flaw was found in Keycloak. An authenticated user with the uma_protection role can bypass User-Managed Access (UMA) policy validation. This allows the attacker to include resource identifiers owned by other users in a policy creation request, even if the URL path specifies an attacker-owned resource. Consequently, the attacker gains unauthorized permissions to victim-owned resources, enabling them to obtain a Requesting Party Token (RPT) and access sensitive information or perform unauthorized actions.
Severity
HIGH
CVSS score
8.1
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-04-02 13:16:27.210000
Last modified
2026-10-26 21:10:00.170000
View original CVE JSON
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"published": "2026-04-02T13:16:27.210",
"lastModified": "2026-10-26T21:10:00.170",
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"value": "Se encontró una falla en Keycloak. Un usuario autenticado con el rol uma_protection puede eludir la validación de políticas de Acceso Gestionado por el Usuario (UMA). Esto permite al atacante incluir identificadores de recursos propiedad de otros usuarios en una solicitud de creación de política, incluso si la ruta URL especifica un recurso propiedad del atacante. En consecuencia, el atacante obtiene permisos no autorizados a recursos propiedad de la víctima, lo que le permite obtener un Token de Parte Solicitante (RPT) y acceder a información sensible o realizar acciones no autorizadas."
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